Apparatus for opening and protecting from contamination heat-sealable bags

ABSTRACT

There is disclosed apparatus for opening and protecting heatsealable bags including spreading means adapted to enter the top of the bag to keep the same open the spreading means have coverings of resilient material which press against sealing zones of the internal surfaces of the bag and thereby prevent air-borne particles from reaching the sealing zones. Suction tubes extending through the resilient material are also provided for extracting air-borne material. The spreading means is slidably carried by a casing for horizontal movement while the casing is vertically slidable on guide rails.

United States Patent [191 Merat Dec. 3, 1974 [5 1 APPARATUS FOR OPENING AND 2,853,842 9/195 8 Vredenburg 53/384 PROTECTING FROM CONTAMINATION 2,899,786 8/1959 Harker 53/187 3,149,649 9/1964 Hix 141/93 HEAT-SEALABLE BAGS Jean-Pierre Merat, 4, rue Robert Giraudineau, Vincennes, France Filed: May 4, 1973 Appl. No.: 357,110

Related US. Application Data Continuation-impart of Ser. No, 799,720, Feb. 17, 1969, abandoned.

Inventor:

References Cited 1 UNITED STATES PATENTS 8/1955 Fox l4l/316X 6/1956 Lorenz et a1. 53/22 B Primary Examiner-Travis S. McGehee Attorney, Agent, or Firm-Ernest G. Montague; Karl F. Ross; Herbert Dubno 5 7 ABSTRACT -particles from reaching the sealing zones. Suction tubes extending through the resilient material are also provided for extracting air-borne material. The spreading means is slidably carried by a casing for horizontal movement while the casing is vertically slidable on guide rails.

2 Claims, 5 Drawing Figures PATENTELEEC 34amv 3,851,444

sum 2 or 2 5 m I L APPARATUS FOR OPENING AND PROTECTING FROM CONTAMINATION HEAT-SEALABLE BAGS 2,899,786; 3,384,134 and in Swiss Pat. No. 308,7ll

such cleaning has been effected by various suction means.

With a view to improving upon prior art devices of the kind above described, the present invention provides apparatus which substantially eliminates the need for cleaning the surfaces to be sealed after filling and which can be installed on any kind of weighing or dispensing equipment for heat-weldable or adhesive bags,

including machines for the automatic or semiautomatic filling of bags.

The apparatus of the invention includes spreading means insertable in the top of a bag consisting of two,

leaf springs slidably mounted for horizontal movement along a carriage itself mounted on a frame for vertical motion whereby the springs can be moved in and out of the baglMeans for making the springs converge toward their center'to open the bag are also provided. Resilient coverings are provided on the springs so that, while the springs are in their bowed condition holding open the top of the bag, the resilient material presses against the sealing zones of the internal surfaces of the bag end thereby preventing air-borne particles from reaching the sealing zones.

The above and other objects will become more readily apparent from the following detailed description given with reference to the accompanying drawing, in which;

FIG. I is a diagrammatic sectional view of parts of an apparatus in accordance with the present invention with a bag prior to filling thereof;

FIG. 2 is a view corresponding to FIG. 1 showing the parts during the filling of the bag;

FIG. 3 is a perspective fragmentary view of those parts of the apparatus which serve in particular for holding the bags;

FIG. 4 is a top plan view, corresponding to FIG. 3, and showing the open position of the bag in solid lines and the closed position in chain-dotted lines; and

FIG. 5 is a front elevational view of an assembly incorporating the invention.

The the apparatus shown comprises a pair of spring blades 4 and a carrier 3 on which the blades are slidably mounted for horizontal movement thereon. Pneumatic or hydraulic means (not shown) are provided for actuating grippers 2 or other means for pushing the ends of the leaf springs or blade 4 towards one another so that they become bowed to hold open the mouth of bag 7 as shown in FIG. 2 and in full lines in FIG. 4. In FIG. 1 are shown two of the grippers 2, portions of which can be seen in FIG. 2, while in FIGS. 3 and 4 are shown only the lower portions of the grippers.

.The carrier 3 is movably supported on slideway or support rails 1 which is actuated by a piston or other pneumatic means (not shown) for vertical movement relative to the mouth of a bag 7 held open below a weighing funnel for the admission of dusty or other substances from the funnel 8 into the bag.'ln operation, the mouth of the bag is placed manually around the blades before these are bowed and while these are in their raised position. As shown in FIG., 5, the bag is supported at its lower end by guide rails 12 while its bot tom rests on a conveying belt 14 for conveying it to a heat welding unit 14' and then out for removal from the assembly.

Some or all of the functions of the apparatus described'may be effected automatically, the feeding and removal of the bags and the movements of the parts of the apparatus being caused in appropriate sequence by known mechanisms incorporated in the machine which usually also will have means for weighing or metering the substances to be introduced into the bags. With simpler machines some of these operations may be effected manually or their order modified. In accordance with the present invention, blades 4 have coverings S of resilient material so that while the blades are in their bowed condition (FIG. 2 and FIG. 4 in full lines) holding the mouth of the bag 7 open this resilient material presses against the upper or sealing surfaces inside the bag to thereby prevent air borne particles from reaching the sealing zones.

The apparatus comprises also a pair of horizontally movable arms 6 forming abutments so that the bag 7 can be tightly clamped between the resilient material 5 and the abutments 6 while the blades 4 are in their bowed condition and hold open the mouth of the bag during filling. The apparatus can also be operated in a different way. The slideway I can be lowered and the blades allowed to return to their original flat or unbowed position and the arms 6 moved toward one another so as to clamp the sealing surfaces of the bag. Then the slideway carrying the blades is raised back to its initial position. As shown the apparatus further comprises a suction system which includes suction tubes 9 extending through the resilient material for the complete extraction of any air-borne particles.

I claim: 1. An apparatus for filling and sealing a bag having an upwardly turned mouth, comprising:

a filling station provided with an outlet; a pair of horizontally extending support rails running from the region of said outlet; a carriage mounted on said support rails and horizontally displaceable thereon from said region to another region;

a bag-sealing station at said other region-for sealing surfaces of a bag spread by said springs. 2. The apparatus defined in claim 1 further comprising at least one suction conduit embedded in said resilient layers for suction removal of particles along the surfaces of said bag juxtaposed with said layers. 

1. An apparatus for filling and sealing a bag having an upwardly turned mouth, comprising: a filling station provided with an outlet; a pair of horizontally extending support rails running from the region of said outlet; a carriage mounted on said support rails and horizontally displaceable thereon from said region to another region; a bag-sealing station at said other region for sealing the mouth of a bag; a pair of leaf springs having opposite extremities lying substantially against one another and mounted on said carriage; means on said carriage for relatively displacing the opposite extremities of said leaf springs toward and away from one another to alternately spread said leaf springs apart between their extremities to spread the mouth of a bag fitted over said leaf springs; resilient layers disposed along at least opposite lateral faces of said leaf springs for contacting internal surfaces of said bag along said mouth for preventing contamination thereof; means displaceable from one of said regions toward the other region for entraining said carriage therebetween along said rails; and horizontally movable abutments at least at the first mentioned region for laterally engaging external surfaces of a bag spread by said springs.
 2. The aPparatus defined in claim 1 further comprising at least one suction conduit embedded in said resilient layers for suction removal of particles along the surfaces of said bag juxtaposed with said layers. 